<template>
    <div class="header">
        <div class="nav">
            <ul class="left-part">
                <li class="logo">
                    <router-link to="/">
                        <img src="../assets/img/head-logo.svg" alt />
                    </router-link>
                </li>
                <li class="ele">
                    <span
                        @click="goPage('/free-course')"
                        :class="{ active: url_path === '/free-course' }"
                    >免费课</span>
                </li>
                <li class="ele">
                    <span
                        @click="goPage('/actual-course')"
                        :class="{ active: url_path === '/actual-course' }"
                    >实战课</span>
                </li>
                <li class="ele">
                    <span
                        @click="goPage('/light-course')"
                        :class="{ active: url_path === '/light-course' }"
                    >轻课</span>
                </li>
            </ul>

            <div class="right-part">
                <div v-if="!username">
                    <span @click="put_login">登录</span>
                    <span class="line">|</span>
                    <span @click="put_register">注册</span>
                </div>
                <div v-else>
                    <span>{{ username }}</span>
                    <span class="line">|</span>
                    <span @click="logout">注销</span>
                </div>
            </div>
            <form class="search">
                <div class="tips" v-if="is_search_tip">
                    <span @click="search_action('Python')">Python</span>
                    <span @click="search_action('Linux')">Linux</span>
                </div>
                <input
                    type="text"
                    :placeholder="search_placeholder"
                    @focus="on_search"
                    @blur="off_search"
                    v-model="search_word"
                />
                <button
                    type="button"
                    class="glyphicon glyphicon-search"
                    @click="search_action(search_word)"
                ></button>
            </form>
            <Login
                v-if="is_login"
                @close="close_login"
                @go="put_register"
                @loginsuccess="login_success"
            />
            <Register v-if="is_register" @close="close_register" @go="put_login" />
        </div>
    </div>
</template>

<script>
import Login from './Login'
import Register from './Register'
export default {
    name: "Header",
    data() {
        return {
            url_path: sessionStorage.url_path || '/',
            is_login: false,
            is_register: false,
            token: '',
            username: '',
            is_search_tip: true,
            search_placeholder: '',
            search_word: ''
        }
    },
    methods: {
        goPage(url_path) {
            // 已经是当前路由就没有必要重新跳转
            if (this.url_path !== url_path) {
                this.$router.push(url_path);
            }
            sessionStorage.url_path = url_path;
        },
        put_login() {
            this.is_login = true;
            this.is_register = false;
        },
        put_register() {
            this.is_login = false;
            this.is_register = true;
        },
        close_login() {
            this.is_login = false
        },
        close_register() {
            this.is_register = false;
        },
        login_success() {
            this.username = this.$cookies.get('username')
            this.token = this.$cookies.get('token')
        },
        logout() {
            //清除cookie
            this.$cookies.remove('token')
            this.$cookies.remove('username')
            //把两个变量值为空
            this.username = ''
            this.token = ''
        },
        search_action(search_word) {
            if (!search_word) {
                this.$message('请输入要搜索的内容');
                return
            }
            //this.$route.params  从路径中取值
            //this.$route.query   从？后面的取
            if (search_word !== this.$route.query.word) {
                this.$router.push(`/search?word=${search_word}`);
            }
            // this.$router.push(`/search?word=${search_word}`);
            this.search_word = '';
        },
        on_search() {
            this.search_placeholder = '请输入想搜索的课程';
            this.is_search_tip = false;
        },
        off_search() {
            this.search_placeholder = '';
            this.is_search_tip = true;
        },
    },
    created() {
        sessionStorage.url_path = this.$route.path;
        this.url_path = this.$route.path;

        //当页面一创建，我就去cookie中取token和username
        this.username = this.$cookies.get('username')   //取到就有值，取不到就为空
        this.token = this.$cookies.get('token')   //取到就有值，取不到就为空
    },
    components: {
        Login,
        Register
    },
}
</script>

<style scoped>
.header {
    background-color: white;
    box-shadow: 0 0 5px 0 #aaa;
}

.header:after {
    content: "";
    display: block;
    clear: both;
}

.slogan {
    background-color: #eee;
    height: 40px;
}

.slogan p {
    width: 1200px;
    margin: 0 auto;
    color: #aaa;
    font-size: 13px;
    line-height: 40px;
}

.nav {
    background-color: white;
    user-select: none;
    width: 1200px;
    margin: 0 auto;
}

.nav ul {
    padding: 15px 0;
    float: left;
}

.nav ul:after {
    clear: both;
    content: "";
    display: block;
}

.nav ul li {
    float: left;
}

.logo {
    margin-right: 20px;
}

.ele {
    margin: 0 20px;
}

.ele span {
    display: block;
    font: 15px/36px "微软雅黑";
    border-bottom: 2px solid transparent;
    cursor: pointer;
}

.ele span:hover {
    border-bottom-color: orange;
}

.ele span.active {
    color: orange;
    border-bottom-color: orange;
}

.right-part {
    float: right;
}

.right-part .line {
    margin: 0 10px;
}

.right-part span {
    line-height: 68px;
    cursor: pointer;
}

.search {
    float: right;
    position: relative;
    margin-top: 22px;
    margin-right: 10px;
}

.search input,
.search button {
    border: none;
    outline: none;
    background-color: white;
}

.search input {
    border-bottom: 1px solid #eeeeee;
}

.search input:focus {
    border-bottom-color: orange;
}

.search input:focus + button {
    color: orange;
}

.search .tips {
    position: absolute;
    bottom: 3px;
    left: 0;
}

.search .tips span {
    border-radius: 11px;
    background-color: #eee;
    line-height: 22px;
    display: inline-block;
    padding: 0 7px;
    margin-right: 3px;
    cursor: pointer;
    color: #aaa;
    font-size: 14px;
}

.search .tips span:hover {
    color: orange;
}
</style>